Research team
Expertise
Dr. Sergio Araujo is currently a postdoc in the Laboratory of Microbiology, Parasitology and Hygiene (LMPH) at UAntwerp and has a distinguished track working with infectious diseases. Up to date he has participated in 14 papers published in internationally recognized peer-reviewed journals (5 of those as first author), including the paper entitled “Molecular evidence for the aerial route of infection of Mycobacterium leprae and the role of asymptomatic carriers in the persistence of leprosy” published in the prestigious journal Clinical Infectious Diseases, which also warranted an editorial commentary in the same journal. He started his post-graduate research trajectory in 2010 when he joined a Master’s degree program in Health Sciences, and obtained his doctorate in the same program by 2016. During his doctorate he also did a 1-year research secondment at the Laboratory Research Branch of the National Hansen's Disease Programs (NHDP) of the United States of America (USA), to develop a molecular drug susceptibility test for the identification of drug resistance in leprosy. After obtaining his PhD, he has held 3 positions as postdoctoral scientist with projects on different scopes (stem-cell regenerative medicine, fungi pulmonary host-pathogen interactions, and vaccine immunology and development), two of them in Brazil (one at a university and the other at a public health research institution), and one at the Cedars-Sinai Medical Center in Los Angeles, USA.
Immunological mechanisms of respiratory co-infections (RespiriCO).
Abstract
Despite the concept that infectious diseases are usually caused by a single pathogen, in reality, we are constantly challenged by multiple pathogens and growing evidence indicates that co-infections are a much more common event than clinically perceived. The respiratory tract is the first point of contact with airborne pathogens and the most common site for infections. Hence, human respiratory infections contribute to substantial morbidity and economic losses worldwide, resulting in approximately 2.5 million deaths each year. Recent findings have shed light on a crucial factor in the severity of respiratory infections: the role of co-infections. Considering the public health importance of respiratory infections and the scarcity of research on the impact of co-infections in the balance of immune defences, this project proposes to study the in vitro and in vivo effects of diverse parasitic, viral, and bacterial co-infections on different types of immune cellsin the lungs, and comprehensively characterize tissue local microenvironment and host-pathogen interactions. Additionally, we will investigate the immunomodulatory effects of protozoan infections on vaccines and chemotherapy treatments and their impact on the protection against targeted pathogens. Objectives include: elucidate the molecular mechanisms underlying immunological responses in the lungs and the susceptibility to co-infections; investigate altered immune responses of vaccines and the changes in the response to co-infection after chemotherapy of the primary infection. In the end, this study will allow deeper understanding of respiratory co infections that could pave the way for the development of improved diagnostic and prognostic techniques, as well as the potential for proposing supportive treatments and vaccines. Notwithstanding, the development of this project will open up new avenues for future co infection research and propel the fellow towards establishment as a successful independent researcher.Researcher(s)
- Promoter: Caljon Guy
- Co-promoter: Cos Paul
- Co-promoter: Delputte Peter
- Fellow: Araujo Sergio
Research team(s)
Project type(s)
- Research Project
Throwing immunity off the scent of the invasion: the role of olfactory ensheating glia in airway infection.
Abstract
This BOF-SRG project aims to support my independent research line, exploring host-pathogen interactions and unraveling pathophysiological mechanisms involved in the intracellular invasion of the olfactory network by understudied neurotropic infectious agents of various aetiologies, that have been found to infect the upper respiratory tract and cause neuropathological manifestations. Currently, as a senior postdoc at the Laboratory of Microbiology, Parasitology, and Hygiene (LMPH), I am leveraging my extensive experience on Hansen's Disease (HD) to investigate the causative pathogen of HD, Mycobacterium leprae. My research in the field of HD has been internationally recognized, and I have published four first-author papers on HD, including two fundamental studies that have shifted the paradigm on the infection mechanism: one unveiling asymptomatic carriage of bacilli in the nose with a potential role in the chain of transmission; and the other on the aerial route as the predominant mode of infection and transmission. The evidence of nasal mucosa infection and high incidence of olfactory dysfunction in HD, as well as the knowledge gap regarding the cellular mechanisms of infection, warrant further investigation. My hypothesis is that M. leprae can infect olfactory ensheathing cells (OECs) and this unexplored niche can be an undisclosed route for the initial invasion of nerve tissues, play a role in immune evasion, and contribute to the colonization of nasal mucosa and the persistence of chronic infection. The development of this project will increase our understanding of this debilitating disease and shed light on the unknown mechanisms by which it can evade immune responses, colonize nerve tissues, and develop chronic disease. It will also provide the cornerstone for establishing an international partnership with research groups in the Global South (Brazil) working on HD and other neglected tropical diseases (NTDs). In the short term, I also plan to explore the infection of OECs by other neurotropic parasitic, viral, and bacterial pathogens under investigation at LMPH, such as Leishmania, RSV, and Streptococcus, which can also invade and damage the PNS and/or use the olfactory pathway as a route of entry into the CNS. In the middle term, I envisage investigating co-infections with pathogens of different aetiologies in the established infection model of OECs. In the long term and beyond infectious diseases, this project will open opportunities for collaboration on regenerative medicine studies, as the use of OECs is also a promising strategy for neuroprotection and the regeneration of neural tissues.Researcher(s)
- Promoter: Araujo Sergio
Research team(s)
Project type(s)
- Research Project
Respiratory co-infection models for fundamental and translational biomedical research.
Abstract
Human respiratory infections lead to a spectrum of respiratory symptoms and variable disease severity, contributing to substantial morbidity, mortality and economic losses worldwide. Respiratory pathogens can spread easily in the population and are specifically prone to cause large scale outbreaks, epidemics and even pandemics. While such pandemics have devastating impact on human health and cause major socio-economic disruptions, the annual burden of respiratory infections such as Respiratory Syncytial Virus (RSV), Mycobacterium tuberculosis and Streptococcus pneumoniae is also substantial. Respiratory infections are worldwide the number one cause of death in children below five years of age, with ~650.000 annual deaths. The disease burden however goes beyond this staggering number, with an overall effect on morbidity and mortality in the general population worldwide (~2.5 million deaths annually). Of particular interest, it has become very clear that severe disease upon respiratory infections not only depends on one particular pathogen, but also depends on other previous or simultaneous co-infections. The importance and impact of co-infection are however not yet fully clear. Therefore, there is an urgent need to enhance our understanding of host-pathogen interactions at the lung (immune) interface and to develop clinically relevant animal models. Laboratory animal studies are a cornerstone of basic research and the development of novel prophylactic, diagnostic and therapeutic modalities. However, the development of suitable infection models can be notoriously daunting, often resulting in very narrow assay windows due to rapid pathogen clearance or early mortality of the host. The research teams involved in this challenge have longstanding expertise with infection models, both in vitro and in rodents. Three PIs focus their research on parasitic (prof. Caljon), viral (Prof. Delputte) and bacterial infections (Prof. Cos) to gain understanding of protective innate and adaptive immune responses, and of (immune) pathology. A recent study in which LMPH was involved demonstrated that some lung bacteria have an immune modulatory role in chronic respiratory diseases (Rigauts et al., Eur. Resp. J., 2022). Very recent parasitological observations show that African trypanosomes rapidly and permanently colonize the lung tissue with substantial changes in the immunological repertoire (reductions in B cells and eosinophils) but without overt respiratory dysfunction or pathology. Surprisingly, RSV challenge revealed a higher susceptibility with an enhanced and sustained viral replication, hinting at complex in vivo interactions that cannot be modelled in vitro (Mabille et al., Nat. Commun., pending acceptance). Exploiting the expertise with parasitic, viral and bacterial infections at LMPH, the established high-end platforms for evaluating lung function and immunological correlates and initiatives of biobanking, this challenge aims to functionally and immunologically characterize pulmonary infections and co-infections of parasitic, viral and bacterial origin. This will provide invaluable information on virulence and pathogenicity of selected strains from in-house collections, establishment of in vivo read-out assays and immunological correlates of induced pathology. Besides progressing basic scientific insights in host-pathogen interactions, the applications are numerous including the development and evaluation of diagnostics and medicinal compounds.Researcher(s)
- Promoter: Caljon Guy
- Co-promoter: Cos Paul
- Co-promoter: Delputte Peter
- Fellow: Araujo Sergio
Research team(s)
Project type(s)
- Research Project